You need direnv installed, then do direnv allow.
Use make setup to generate the values file (values.config).
Then, fill out all necessary variables. You can find examples for each var.
Once the values.config file is filled out, use:
git-config
If you don't want to use the values.config file, you can execute the script in interactive mode using:
git-config -i
You will be prompted for the necessary variables.